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Evaluating Stormwater Pollutant Removal Mechanisms by Bioretention in the Context of Climate ChangeCording, Amanda 01 January 2016 (has links)
Stormwater runoff is one of the leading causes of water quality impairment in the U.S. Bioretention systems are ecologically engineered to treat stormwater pollution and offer exciting opportunities to provide local climate change resiliency by reducing peak runoff rates, and retaining/detaining storm volumes, yet implementation is outpacing our understanding of the underlying physical, biological, and chemical mechanisms involved in pollutant removal. Further, we do not know how performance will be affected by increases in precipitation, which are projected to occur in the northeastern U.S. as a result of climate change, or if these systems could act as a source or sink for greenhouse gas emissions.
This research examines the design, construction, and development of monitoring methods for bioretention research, using the University of Vermont (UVM) Bioretention Laboratory as a case study. In addition, this research evaluates mobilization patterns and pollutant loads from road surfaces during the "first flush" of runoff, or the earlier part of a storm event. Finally, this research analyzes the comparative pollutant removal performance of bioretention systems on a treatment by treatment basis.
At the UVM Bioretention Laboratory, eight lined bioretention cells were constructed with monitoring infrastructure installed at the entrance and at the subterranean effluent. A conventional, sand and compost based, bioretention soil media was compared to a proprietary media engineered to remove phosphorus, called Sorbtive Media™, under simulated increases in precipitation. Two drought tolerant vegetation mixes, native to the northeast, were compared for sediment and nutrient retention. Each treatment was sampled for soil gas emissions to determine if it was a source or a sink.
The monitoring infrastructure designs used in this research allowed for the effective characterization of pollutant mass loads entering and exiting bioretention. Cumulative mass loads from stormwater were found to be highest for total suspended solids, followed by total Kjeldahl nitrogen, nitrate, non-labile phosphorus and soluble reactive phosphorus, in descending order by mass. Total suspended solids, total Kjeldahl nitrogen, and non-labile phosphorus mass were well retained by all bioretention treatments. However, the compost amendment in the conventional soil media was found to release labile nitrogen and phosphorus, far surpassing the mass loads in stormwater. When compared with conventional media, Sorbtive Media™ was highly effective at removing labile phosphorus and was also found to enhance nitrate removal. Systems containing deep-rooted vegetation (Panicum virgatum) were found to be particularly effective at retaining both labile and non-labile constituents. Overall, none of the bioretention treatments were found to be a significant source of N2O and were small sinks for CH4 in most treatments.
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Evaluating Alternative Technologies And Monitoring Methods For Water Quality In A Field Setting; Research On Effects On Phosphorous And Solids Removal From Cheese Factory Wash Water And Stormwater Runoff TreatmentAllen, Dana J. 01 January 2017 (has links)
Lake Champlain is a major economic driver for Vermont's tourism economy, as well as a primary source of drinking water for many of the state's residents but nutrient pollution represents a potential threat to ecosystem health and economic well-being. From December 2011 to December 2012 a field trial of an EAF steel slag filter was assessed for its feasibility in treating wastewater originating from Swan Valley Cheese (SVC), in Swanton, VT. The study focuses on a period of the filter's operation from May 4 to October 10, 2012. The plant generates approximately 20,000 gallons per day of high P concentration wash water which is treated in an open aerated lagoon. The filter treated effluent from this lagoon. The major goals of this research were to conduct a field trial of an EAF steel slag filter to evaluate its effect on total P (TP), dissolved reactive P (DRP), and total suspended solids (TSS). Research was also conducted on pH reduction for filter effluent.
Results indicate that the filter removed 95.83% of TP, 96.65% of DRP, and 52.25% of TSS. Average pH effluent was measured at 10.12 ±1.55.
Additionally, a field study was conducted on sampling two unlined bioretention systems treating urban stormwater runoff. Methods used are presented and methodological considerations for future studies are presented to guide researchers in more effective and efficient methods for obtaining influent and effluent samples from bioretention systems that are not necessarily designed for sampling.
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Geographical Information Systems (GIS) Applied to Urban Nutrient Management: Data Scarce Case Studies from Belize and FloridaHaberstroh, Charlotte Juliane 16 March 2017 (has links)
Nutrient inputs into the environment greatly impact urban ecosystems. Appropriate management strategies are needed to limit eutrophication of surface water bodies and contamination of groundwater. In many existing urban environments, retrofits or complete upgrades are needed for stormwater and/or wastewater infrastructure to manage nutrients. However, sustainable urban nutrient management requires comprehensive baseline data that is often not available. A Framework for Urban Nutrient (FUN) Management for Geographic Information Systems (GIS) was developed to specifically address those areas with limited data access. Using spatial analysis in GIS, it links water quality, land use, and socio-demographics, thereby reducing data collection and field-based surveying efforts. It also presents preliminary results in a visually accessible format, potentially improving how data is shared and discussed amongst diverse stakeholders. This framework was applied to two case studies, one in Orange County Florida and one in Placencia, Belize.
A stormwater pond index (SPI) was developed to evaluate 961 residential wet ponds in Orange County, Florida where data was available for land use and socio-demographic parameters, but limited for water quality. The SPI consisted of three categories (recreation, aesthetics, education) with a total of 13 indicators and provided a way to score the cultural and ecosystem services of 41 ponds based on available data. Using only three indicators (presence of a fence, Dissolved Oxygen (DO) < 4 mg/l, and water depth < 3 ft), 371 out of 961 stormwater ponds were assessed. Additional criteria based on socio-demographic information (distance to a school, population density, median household income under $50,000, percentage of population below the poverty line, and distance to parks) identified seven wet ponds as optimum for potential intervention to benefit residents and urban nutrient management purposes.
For the second case study, a water quality analysis and impact assessment was performed for the Placencia peninsula and lagoon in Belize. This study had access to water quality data, but limited land use data and very limited socio-demographic data. Since May 2014, water quality samples have been taken from 56 locations and analyzed monthly. For this study, Dissolved Oxygen (DO), Nitrate (NO3--N), Ammonia (NH3), Chemical Oxygen Demand (COD), and 5-Day Biochemical Oxygen Demand (BOD5), Escherichia coli (E. coli), and Enterococci were selected to assess spatial and temporal variation of water quality in the groundwater on the peninsula as well as the surface water in lagoon, estuaries and along the coast. A spline interpolation of DO, Nitrate, BOD5, and COD for June 2016 indicated the concentration distribution of those parameters and areas of special concern. A spatial analysis was conducted that showed that Nitrate and Enterococci exceeded the effluent limits of Belize very frequently in the complete study area while the other parameters contributed to the identification of key areas of concern. As a high variability of concentrations over time was observed, a temporal analysis was conducted identifying a link between the water quality data and two temporal impact factors, rainfall and tourism. The two case studies showed the broad and flexible application of the FUN management for GIS and the great advantages the use of GIS offers to reduce costs and resources use.
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Characterization, toxicity and treatment of wood leachate generated outdoors by the wood-based industry / Karakterisering av toxicitet och behandling av lakvatten från trä som genererats utomhus vid träbaserade industrierSvensson, Henric January 2014 (has links)
Wood is a natural raw material, and would hardly be considered a risk to the environment. However, the handling of wood materials on an industrial scale has been shown to have a negative impact on water bodies that run-off from industrial sites that process wood-based materials. Most investigations related to water pollution from wood-based industries have focused on large industrial sites such as pulp and paper mills. The goal of the present thesisis to understand better such environmental problems and treatment solutions that occur at most wood handling sites. Where there are large outdoor storage areas for logs and sawdust that are exposed to rainfall or irrigation, such as the wooden-floor and bio-energy sectors. Leachate generated by the contact of water with wood in storage areas contains a large amount of organic matter that is potentially hazardous to water bodies that receive run-off from the site. It has been found that different wood species yield different leachate compositions, with leachate from oak having the highest pollutants content, followed by leachate from pine. This investigation shows that oak has the potential to leach about 10 times the amount of polyphenols compared with other investigated species (i.e., pine, beech and maple). Furthermore, oak leachates have the lowest ratio of biological oxygen demand at 7 days tochemical oxygen demand (0.12), which suggests a potential problem with the biological degradation of this leachate. It has also been shown that leachate from wood are potentially toxic to aquatic organisms. Treatability studies with the aim of reducing the environmental impact of wood leachate were conducted on a pilot scale as part of the scope of this thesis. The results showed, among other options, the possibility of using constructed wetlands to treat leachate. It was found that plants and aeration can affect the performance of a wetland. However, the most important factor is the time water spends in the wetland. Filter material that could be used to absorb leachate was also studied. A filter consisting of a mixture of peat and ash (from incinerated organic matter), was used to absorb a specific chemical group (polyphenols) in the leachate. It was also shown that polyphenols are vulnerable to ozone, representing a third viable treatment process. / Trä är ett naturligt råmaterial som knappast anses vara en risk för miljön. Däremot har hanteringen av trämaterial i industriell skala visat sig ha negativ inverkan på vattendrag. De flesta utredningar avseende vattenföroreningar inom träbaserade industrier har fokuserat på stora industrier med stor vattenförbrukning så som massa- och pappersbruk. Lakvatten som alstras vid kontakten mellan vatten och trä innehåller höga halter av organiska ämnen som är potentiellt farliga för vattendrag. Målet med denna avhandling är att få kunskap om ovanstående miljöproblem och möjlig behandlingar av dessa. Förorenat lakvatten skapas av industrier, där stora mängder timmer och sågspån är placerade utomhus och utsätts för regn och bevattning, såsom inom trägolv och bioenergisektorn. Man har funnit att lakning från olika träslag ger olika sammansättningar på lakvattnet, där lakvatten från ek har den högsta halten av föroreningar följt av furu. Denna undersökning visar att ek har potential att laka ut tio gånger så mycket polyfenoler jämfört med andra undersökta arter (tall, bok och lönn). Dessutom har lakvatten från ek den lägsta andelen av biologisk syreförbrukning efter 7dagar per kemisk syreförbrukning (0,12), vilket tyder på ett potentiellt problem med den biologiska nedbrytningen av detta lakvatten. Man har även påvisat att lakvattnet från trä är potentiellt giftigt för akvatiska organismer. Studier för att försöka minska miljöpåverkan av lakvatten från denna trädsort gjordes i pilotskala inom ramen för denna avhandling. Dessa studier visade bland annat på möjligheterna att använda sig av våtmarker som reningsmetod, där växter och luftning påverkar hur bra en våtmark fungerar. Men den viktigaste faktorn var den ökade uppehållstiden som vattnet får i våtmarken. Utöver studier av våtmarker har också ett filtermaterial studerats, filtret bestod av en blandning av torv och aska, som användes för att absorbera en specifik kemisk grupp i lakvattnet (polyfenoler). I en tredje typ av behandlingsprocess visade det sig också att polyfenoler effektivt kan brytas ned av ozon.
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Inläckage i spillvattenledningar i Rengsjö : En utredning baserad på ammoniummetodenThor, Elin January 2016 (has links)
Denna studie handlar om en metod som används för att lokalisera inläckage av tillskottsvatten på spillvattennät. Grunden är de praktikperioder som författaren har haft hos VA-bolaget Helsinge Vatten AB och då det utförts flera försök till att utreda inläckage i spillvattenledningarna. Metoden går ut på att analysera koncentrationen av ammonium i flödet som hämtas från brunnarna ute på nätet. Analyserna sker med hjälp av en portabel spektrofotometer tillsammans med reagenskyvetter som analyserar koncentrationen på bara 15 minuter. Detta ger en indikation på hur utspätt spillvattnet är, om det är utspätt av tillskottsvatten så visar analysen ett lågt värde vilket tyder på inläckage av dagvatten, grundvatten eller dricksvatten. Denna metod är framtagen av Norrköping Vatten och Avfall som har lyckats bra med att lokalisera inläckage med metoden. Norrköping Vatten och Avfall är en stor källa till denna studie med sin rapport ”Minskning av in- och utläckage genom aktiv läcksökning”(Uusijärvi, 2013). I rapporten redovisas de ammoniumanalyser som har gjorts med tillhörande diagram för att tydliggöra resultaten. Eftersom spillvattennät ofta hör samman med pumpstationer och reningsverk som påverkar elförbrukning har statistik tagits fram för den pumpstation som analysområdet hör samman med. Elförbrukning har jämförts med nederbördsmätning för att se om ledningsnätet är påverkat av nederbörd, eftersom pumpstationen får arbeta mer om det är tillskottsvatten i ledningarna. För att få fram en uppskattad mängd inläckage så har en beräkning gjorts med hjälp av en mall som Norrköping vatten och avfall har tagit fram. Där används analysvärden som tyder på inläckage tillsammans med antal abonnenter, ledningssträcka och storförbrukares avlopp. Tillsammans blir det ett värde på uppskattat inläckage i liter per dygn och meter ledning(L/D/M). I rapporten finns det tre områden som ingår i byn Rengsjö som är utredda med ammoniummetoden. I ett testområde blev resultatet inte som önskat men lärorikt för personalen. Ett område gav resultat som visar på god kvalitet av nätet med en jämförelse av torr- och regnväder. Samt ett område där ett troligt inläckage upptäckts som kommer utredas vidare under sommaren. Detta fynd kan ge stora mängder tillskottsvatten, vilket uppfyller delar av de mål som formulerats i rapporten, dvs. att hitta inläckage för att planera vidare utredning. Tillsammans med resultaten för varje område finns en omfattande diskussion där alla aspekter som påverkar de uppmätta analysvärdena tas upp. Som slutsats konstateras ammoniummetoden som mycket framgångsrik i syfte för Helsinge Vatten att systematiskt kunna kartlägga och utreda sina spillvattennät. Det är en kostnadseffektiv och inte så resurskrävande metod som företaget själv kan använda på en lagom nivå. / This study aims to locate the intrusion of excess water in the sewage networks, analyzing the concentration of ammonium in the flow that is obtained from the wells in the network. The foundation for the work is the author’s previous attempts to investigate stormwater at the VA-company Helsinge Vatten AB. The analysis is carried out by using a portable spectrophotometer with such reagents that can measure ammonium concentration in just 15 minutes. This gives an indication of how diluted effluent is. If it is diluted by excess water the analysis shows a low value which is indicating intrusion of possibly surface water, groundwater or drinking water. This method is developed by Norrköping vatten och avfall, who have been a major reference of this report, with their study “Minskning av in- och utläckage genom aktiv läcksökning”(Uusijärvi, 2013). Results from the ammonium analyses have been presented with associated charts. Because the sewage networks often are associated with pumping stations and wastewater treatment plants, which effect the electricity consumption, the electricity consumption has been documented for the pump stations in the area of study. The electricity consumption increases when the pumps are working. A analysis has been made by comparing the electricity consumption and the precipitation to see if the sewage network is influenced by precipitation. In order to obtain an estimated amount of excess water intrusion, a calculation have been made by using a template produced by Norrköping Vatten och Avfall. In the calculation, values indicating water intrusion along with the number of subscribers, management and those who discharge most wastewater have been used. Together it gives a result of estimated intrusion in liters per day and meter network (L/D/M). In the report, three areas located in the village Rengsjö have been investigated by using this method. The first area where the outcome was not as desired, but very instructive for the staff. The second area gave results that show the good quality of the net with a comparison of dry and wet weather. And also an area where a likely intrusion is detected and will be investigated further during the summer. This finding can indicate large amounts of stormwater. Those findings compiles with parts of the objectives formulated in the report, to find the intrusion and to plan for further investigation. Together with the results for each area, include an extensive discussion in which all aspects that influence the measured analyses have been taken up. The report shows that the ammonium method has been proved to be successful in identifying excess water intrusion in Helsinge Vatten’s sewage networks. This method does not rely on many resources, and therefore it is suitable for companies that wish investigate excess water instruction in a cost-effective way.
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Förbättringsförslag till Kanalen i Sandviken : SWOT-analys av förbättringsförslagenLööv, Amanda January 2016 (has links)
The urban area of Sandviken is founded on industries, which also is the driving force of growth throughout the years. The industry were in need of a nearby and easily accessed water source, and therefore a channel was excavated. The name of that channel today is Kanalen and it has three uses: stormwater recipient, natural element and cultural heritage.The environmental load on Sanvikens urban areas are increasing along with Sandvikens population. This lead to issues regarding the possibility to maintain Kanalen and all its three functions in the future. The purpose of this paper is to present suitable improvements that can be made based on the present situation, limited to traffic and solid waste disposal. The physical boundary of Sandvikens community is Sandvikens’ northern urban part. The goal is to obtain knowledge of both the present situation as well as suitable improvements. To understand the so-called Strength, Weaknesses, Opportunities and Threats(SWOT) analysis is also an interest. The target group is foremost the public servants in the community, however it could also be local residents. The method and method implementation are presented in chronological order in the paper. The literature study is based on several annual reports and secondary literature, as well as database research. Visits to Kanalen were performed in order to take relevant photos and make realistic observations on the physical conditions in and around Kanalen. Interviews took place with people who could contribute to the comprehension of the complexity of Kanalen. Both regarding its significance and additional information. SWOT is the analysis used on the suggested improvements eligibility for Sandviken. The tool was consistent throughout each of the improvements suggested. The results section of the paper is meant to function as an informative foundation and a foundation up for discussion. The description of the current situation consists of figures, pictures and substance levels. The description has two main parts. The first includes the physical aspects of Kanalen and surrounding territory. Points of emission from storm drains to Kanalen and aspects of each function as presented. Further information in that chapter of the paper include an earlier event of landslip and Sandvikens green area. Focus then move to traffic and waste pollution. Specific points of pollution from traffic are roundabouts, traffic lights, and paved roads going directly across Kanalen using bridges. Leaked substances from traffic were found mainly to be nutrients like nitrogen and phosphorus, and heavy metals. The solid waste studied in this paper was concentrated on paths in very close proximity to Kanalen, which is used for walking and biking. The outcome of mapping these paths showed that all waste containers were suitable for the intended task. The environmental impact of nutrients and heavy metals retrieved from the annual report were described in general terms. The reason is to show the risks involved with unsupervised and increasing substance levels. Four improvements on traffic pollution and three on waste are presented in the result section. The improvements to traffic pollution to Kanalen in Sandvikens urban area were degreasers, bio-indicators, permeable pavement coatings and plant beds. These improvements could lead to the following positive effects, less downstream work, enhanced esthetical value despite change, and a lasting heritage. The improvements on waste pollution to Kanalen in Sandvikens urban area were to rectify unsuitable waste containers, implement new and improve illumination along Kanalen. These improvements could lead to following positive effects, preferable biological conditions, less visible waste, and the use of modern solutions that are future friendly. Possible errors associated with this study can be choice of method, use of figures and tables and content that maybe should have been included. However, the following conclusions canebe made from this study. The environmental strain could be reduced if suggested improvements are carried out. The advantages concern all three functions of Kanalen. The proportions of each improvement have an effect on the feasibility. Budget and possibility to coordinate are also decisive elements. This work is meant to lead to environmental advantageous change, both in the aquatic setting in Kanalen as well as in its physical surroundings. / Sandvikens tätort är byggd kring industrin som fick den att börja växa. Industrin behövde en vattenkälla vilket innebar att en kanal grävdes fram. Kanalen är namnet idag och har tre funktioner: dagvattenrecipient, naturinslag och kulturarv. Miljöbelastningen ökar i samband med att tätorten och Sandvikens invånarantal växter. Detta innebär problematik beträffande möjligheten att bibehålla Kanalens tre funktioner även i framtiden. Syftet med arbetet är att presentera förbättringar som kan göras baserat på nuläget vid Kanalen, avgränsat till trafik och avfallsområdena. Sandviken norra tätort är den fysiska avgränsningen i kommunen. Målen är att erhålla kompetens om både dagsläget och lämpliga förbättringar, samt att förstå Strength, Weaknesses, Opportunities and Threats(SWOT) till bästa förmåga. Målgruppen är främst Sandvikens kommun men kan likväl vara residenter i kommunen. Metoden och genomförande av metoden presenteras i kronologisk ordning. Litteraturstudien innehåller årsrapporter och sekundärlitteratur, samt databassökning på internet. Studiebesök gjordes på Kanalen för att ta fotografier och erhålla en verklighetsuppfattning av de fysiska förhållandena i och kring Kanalen. Intervjuer gjordes med personer som kunde bidra till förståelsen av Kanalens komplexa betydelse inom kommunen och kompletterande fakta. SWOT är analysmetoden vald för att analysera rekommenderade förslagens lämplighet. Analysverktyget användes konsekvent på varje förbättringsförslag. Resultatdelen med SWOT är menat att fungera som ett informativt underlag och underlag upp för diskussion. I nulägesbeskrivningen presenteras dagsläget på Kanalen med figurer, bilder och substansnivåer. Nulägesbeskrivningen är uppdelad i två huvuddelar. Första delen beskriver Kanalens fysiska utformning och de tre funktionerna. Utsläppspunkter från dagvattenledningarna till Kanalen visas, samt andra tillhörande aspekter av varje funktion. Ett tidigare ras på Kanalen och Sandvikens grönområde förekommer. Därefter presenteras föroreningskällorna trafiken och avfall. Punkter för utsläpp från trafiken som leder till trafikdagvatten i Sandvikens norra tätort är rondeller, trafikljus och vägar som går direkt över Kanalen via broar. Läckageämnen från trafiken pekade på bland annat näringsämnena kväve och fosfor, samt tungmetaller. Avfallsdelen koncentrerades till gång- och cykelbanorna i direkt anslutning till Kanalen. Utfallet från kartläggningen visade att alla sopkärl inte var optimala för ändamålen. Miljökonsekvenserna av näringsämnen och tungmetaller funna i årsrapporterna beskrevs för att visa riskerna involverade med okontrollerade och ökande nivåer. Resultatdelen med en förklaring av förbättringsförslagen och SWOT-analyser innefattar fyra förbättringsförslag på trafiken och tre förslag på avfall. Förslagen gällande trafiken är oljeavskiljare, bioindikatorer, genomsläppliga beläggningar, och växtbäddar. Föregående förslag kan leda till följande positiva konsekvenser, mindre nedströmsarbete, ökat estetiskt värde trots förändring, och ett hållbart arv. Förslagen gällande avfall är åtgärda befintliga sopkärl, introducera nya och förbättra belysningen. Effekterna kan leda till följande positiva konsekvenser, bättre biologiska förhållanden, mindre synligt avfall och moderna lösningar som kan hålla inför framtiden. Felkällor i arbetet exponeras efterföljande kapitel och berör ämnen som metodval, figur och tabellhantering, och innehåll som eventuellt borde ha inkluderats men inte gjorts. Från arbete kan följande slutsatser utvinnas. Miljöbelastningen kan minskas om förbättringsförslagen utförs. Fördelarna berör alla Kanalens tre funktioner. Omfattningarna av förslagen påverkar hur genomförbara förslagen i tätorten är. Budget och möjligheten till samordning är också faktorer som har avgörande roller. Arbetet är menat att förändra på ett miljöfördelaktigt
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Multikriterieanalys av dagvattenreningstekniker : Med fokus på Västra vägen i GävleEngberg, Joakim January 2016 (has links)
Gävle municipality strives to treat all stormwater that may prevent river and lakes from achieving a good water status under the EU water framework directive. There are three stormwater outflows at Västra vägen in Gävle that discharge untreated stormwater to Gavleån. Gävle municipality has an ambition to clean stormwater as close to the source as possible. The purpose of this study is to conduct a multi-criteria analysis to identify stormwater treatment solutions that are suitable from a technical, ecological, economic and sociocultural perspective. According to EU water framework directive Gavleån does not achieve a good chemical and ecological status because of the presence of contaminates in the river. The alternatives that will be evaluated in the multi-criteria analysis consists of a screen pool, percolation storage and four different types of filters. Except these six solutions a null alternative will be included to evaluate if the situation does not change and the stormwater is not treated as it is today. These seven alternatives will be evaluated by a panel that consists of people who work with stormwater or with matters related to the categories in the multi-criteria analysis. The panel's main priority of categories and criteria is produced by the average value of all participants’ weightings and ratings. The most important category was considered to be the sociocultural perspective and the least important was the technical perspective. The criteria that were considered important for the respective categories were operating and maintenance cost (economic perspective), reduction of pollution (technical perspective), environmental impact, land use (ecological perspective, shared position), and outdoor recreation (sociocultural perspective). The option that received the highest score in the analysis was null alternative followed by the screen pool. That is because the null alternative is considered to have the most positive impact on the socio-cultural perspective, ecological perspective and financial perspective while screen pool scored highest in the technical perspective. The results of the MCA should also be interpreted by different stakeholders' priorities and can be seen in Section 6 in which the scoring of all treatment alternatives are reported. / Gävle kommun strävar efter att rena allt dagvatten som kan försvåra möjligheten att sjöar och vattendrag uppnår en god status enligt EU:s vattendirektiv. Det finns tre dagvattenutlopp vid Västra vägen i Gävle som släpper ut orenat dagvatten till Gavleån. Detta dagvatten har Gävle kommun en ambition av att rena genom ett lokalt omhändertagande så nära källan som möjligt. Syftet med denna studie är att genomföra en multikriterieanalys för att identifiera lösningsåtgärder som kan anses som lämpliga utifrån ett tekniskt, ekologiskt, ekonomiskt och sociokulturellt perspektiv. Enligt EU:s vattendirektiv så uppnår inte Gavleån en god kemisk och ekologiskt status på grund av föroreningar som påträffats under mätningar i ån. Alternativen som kommer att utvärderas i multikriterieanalysen består av en skärmbassäng, perkolationsmagasin samt fyra olika gatubrunnsfilter. Förutom dessa alternativ så inkluderas även ett nollalternativ som avser att ingen förändring sker där dagvattnet inte renas. Dessa sju alternativ kommer att viktas av en viktningsgrupp som består av personer som på olika sätt arbetar med dagvatten eller med frågor som är relaterade till kriterierna i multikriterieanalysen. Viktningsgruppens prioriteringar av kategorier och kriterier framställs genom medelvärdet av alla deltagares betygsättning. Den viktigaste kategorin ansågs vara det sociokulturella perspektivet och den minst viktiga var det tekniska perspektivet. Kriterierna som ansågs viktiga för respektive kategori var drift och underhållskostnad (ekonomiskt perspektiv), reducering av föroreningar (tekniskt perspektiv), miljöpåverkan, markanvändning (ekologiskt perspektiv, delad plats), och rekreation och friluftsliv (sociokulturellt perspektiv). Alternativet som fick högst poäng i viktningen var nollalternativet som blev följt av skärmbassäng. Nollalternativet ansågs ha mest positiv inverkan på det sociokulturella perspektivet, ekologiska perspektivet och ekonomiska perspektivet medans skärmbassäng fick högst poäng under det tekniska perspektivet. Resultatet av multikriterieanalysen ska tolkas efter olika intressenters prioriteringar och kan göras i avsnitt 7 där poängsättningen av alla reningstekniker redovisas.
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Playscape affordances: encouraging experiential learningPankratz, Karissa Rachelle January 1900 (has links)
Master of Landscape Architecture / Department of Landscape Architecture/Regional and Community Planning / Mary Catherine (Katie) Kingery-Page / According to Barbara Hendricks, play environment designer and consultant, “If we want children to grow up with a zest for living we need to give them living spaces that express life as a grand experience.” Hendricks emphasizes playtime is important for children to process formal lessons (Hendricks 2011). This applied design research project seeks to facilitate child development through an experiential learning playscape while addressing stormwater management for Bluemont Elementary School.
The central research question of this project is:
How can school playgrounds be designed to afford children improved social interactions and experiential learning?
An exploration of landscape affordances theory (Sanseter and Hansen 2009, Heft 1988) and experiential learning (Kolb 1984), combined with social interactions and cognitive child development (Addo-Atuah 2012), formed a theory base for the project. Playground observations, stakeholder surveys, stakeholder interviews, and site inventory and analysis informed the eventual design.
Major factors influencing students’ play include age, playground rules, equipment available for use, and weather. Site conditions, including topography and site drainage, can also influence students’ play. In current conditions, stormwater is a schoolyard liability restricting play and safe site circulation.
The researcher gathered insights from student surveys, playground observations, teacher interviews, and site inventory and analysis to complete a comprehensive master plan. The comprehensive master plan and detailed stormwater management plan address the schoolyard over the next twenty to fifty year outlook. The designs resolve practical issues while increasing the variety of site educational and play affordances available to students and teachers for play and learning. A primary goal of the detailed plan is to convert stormwater schoolyard liabilities into amenities and educational tools.
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Burning bridges, reinventing the American lawn: a strategic approach to residential stormwater managementSanders, Christopher L. January 1900 (has links)
Master of Landscape Architecture / Department of Landscape Architecture/Regional and Community Planning / Timothy Keane / Wildcat Creek watershed in Riley County, Kansas has been scene to increasingly severe and damaging flooding in recent years. Significant flood events in the summer of 2010 and 2011 have prompted the community to action. One of many areas of concern is addressed by this project in order to facilitate community efforts to reduce future flooding.
Residential stormwater best management practices (BMPs) implemented by property owners to reduce the amount of stormwater runoff entering the Wildcat Creek watershed is the focus of this project. An analysis of the residential development typology in the City of Manhattan within the Wildcat Creek watershed guides stormwater BMP implementation strategies.
GIS identified residential development types based on land use, land cover, and parcel size. Single family residential and high density multi-family developments are the areas of focus. Rational method stormwater calculations were conducted on one sample site selected from each of four areas identified as unique within the residential context. The four sample sites include large lot single family, small lot single family, traditional single family, and high density multi-family. The current stormwater runoff situation was constructed for residential areas of Manhattan within the Wildcat Creek watershed using these samples.
Sample sites were evaluated four times. Existing stormwater runoff amounts for each site were determined. A minimal BMP treatment in the form of rain gardens was applied. Then a moderate BMP treatment including rain gardens, rain barrels, and native plantings was applied. The fourth evaluation was on a high level of rainwater BMP treatment including rain gardens, rain barrels, cisterns, native vegetation, bioretention, and permeable paving.
Post-BMP runoff calculations were performed. The resulting data was compared to the pre-BMP stormwater data to determine the impact of varying degrees of BMP treatments.
This work produced a series of BMP strategies specifically suited to the Wildcat Creek watershed. These site specific strategies are a valuable resource for community members to help reduce flooding in the watershed. The resulting calculations are also valuable tools for community leaders determining the value of stormwater regulations that may require or promote stormwater BMPs in Manhattan.
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Implementation of a rainwater harvesting network to manage stormwater runoff in Manhattan, KansasMusoke, Elizabeth January 1900 (has links)
Master of Regional and Community Planning / Department of Landscape Architecture and Regional and Community Planning / Tim Keane / The City of Manhattan, Kansas has been subject to intense flooding in the last couple of years. Areas of the city, within the Wildcat Creek Watershed, have been adversely affected. The City of Manhattan and stakeholders from various walks of life are looking for solutions to alleviate flooding within the area. This Master’s Project looks into rainwater harvesting as one of the solutions to help reduce stormwater runoff and contribute to the alleviation of flooding within the Watershed. Rainwater harvesting is increasingly being recognized as an effective way to reduce stormwater runoff. The project explores the potential benefit of using a network of rainwater harvesting elements, namely rain barrels and cisterns supplemented by rain gardens and other infiltration methods to reduce runoff in the City of Manhattan, Kansas.
To assess the benefit of using rainwater harvesting in the City, a neighborhood scale site was chosen and divided into land use types. Three phases were used to assess the impact and implementation of rainwater harvesting. Phase I calculates the volume of runoff generated from each land use type and how much of that runoff can be harvested from the rooftops. The values from the neighborhood scale analysis were then extrapolated to see the impact of rainwater harvesting on a larger scale. Phase II looks at the configuration of a rainwater harvesting system for the structures in each land use type and rainwater reuse options. Finally, Phase III looks at policies, regulations and incentives that can be employed by the City of Manhattan to help encourage rainwater harvesting. This Master’s project seeks to educate the City and its residents about the benefits of rainwater harvesting as a stormwater management tool and provide steps towards potentially using rainwater harvesting as a way to reduce runoff, and help alleviate flooding in the Wildcat Creek Watershed.
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